A light emitting diode (LED) is a type of semiconductor diode. It can convert electric energy into the luminous energy and emit visible light in yellow, green, blue, and the like, as well as invisible infrared and ultraviolet light.
In recent years, high-power LEDs have become a key development concern by factories to meet lighting demands. In conventional high-power normal-chip LEDs, in general, the light emitting unit is a single chip featured with high current and low voltage, and the light emitting efficiency is affected by the raising junction temperature when big current is injected to the chip. In recent years, integrated high-voltage LEDs consisting several low-power LEDs have been introduced by big international factories, in which, the insulating layer is filled into an opened groove and plated with metal and an integrated LED is made after serial or parallel connection. Under serial connection, a low current passes through the small LED units and a high-voltage and low-current LED is formed. Compared with high-voltage diodes by wiring several light emitting diodes in series, the high-voltage light emitting diode has lower thermal resistance, which requires smaller heat dissipation modules in lighting fixtures.
According to Chinese patent CN03820622.6, an integrated light-emitting device is disclosed, where several LED arrays are formed in a two-dimensional single chip on an insulating substrate like sapphire, and overhead bridge wiring is made between single LEDs and between the LED and the electrode. High drive voltage and low drive current are obtained through zigzag-shaped configuration of LED arrays. Problems exist in this integrated light-emitting device, like low light emitting efficiency, difficult heat dissipation, low power and poor reliability. Each independent LED is separated from its adjacent LEDs by etching an N-type semiconductor layer to the insulating substrate surface. Serial wires have to pass through the groove with extremely large height difference, easily causing disconnection of wires during fabrication and making the entire diode impossible to be connected.